Global Three‐Dimensional Simulation of Magnetospheric Dynamics During the Extreme Geomagnetic Storm of 10–11 May 2024

Abstract

This study presents a high‐resolution three‐dimensional global magnetohydrodynamic (MHD) simulation of the historic geomagnetic storm of 10–11 May 2024, using observational data for the ACE solar wind input. This extreme event was characterized by intense solar wind dynamic pressure (∼50 nPa) and exceptionally strong interplanetary magnetic field (IMF) components. The simulation results show key features of the magnetospheric configuration and localized energy dynamics under extreme driving conditions. The strong solar wind dynamic pressure severely compressed the bow shock and dayside magnetopause to within geosynchronous orbit (GEO). During periods of large IMF B _y , even under small or northward IMF B _z conditions, strong magnetospheric compression allows IMF lines to interact and reconnect with the strong geomagnetic field at the high‐latitude flanks, thereby helping to maintain the magnetopause near the GEO regions. In addition to these global boundary responses, the simulation results showed localized, small‐scale phenomena, including the formation of a ∼4 R _E plasmoid in the magnetotail and vortices at the magnetopause. Detailed analyses of these structures indicate complex electromagnetic energy conversion processes (e.g., localized J⋅E signatures) that drive their evolution. These results clarify how the magnetosphere transfers energy and plasma through reconnection and boundary instabilities during severe geomagnetic storms.